Overall, this is a fairly nice lens. It is much less expensive than the Canon version, and provides very good image quality. It is fairly sharp wide open, almost as sharp as the Canon version. The out-of-focus areas are very nice, even when stopped down thanks to the 9-bladed aperture.

The Hypersonic-Motor is pretty fast and quiet, yielding fairly quick and accurate AF. The distance scale is large and easy to read.

The tripod collar included with the lens is much better than the Canon version since you don't have to remove the lens in order to remove the tripod collar, which is very very handy, and a clever design.

Build Quality is pretty nice. It feels pretty solid, but uses more plastic components on the outer barrel than the Canon versions, making it weigh less. Although it uses plastic, it is still fairly tough, and the rear section is metal.

Biggest complaint, the Sigma EX finish. It's fairly grippy, which is nice, until it starts to flake off. And trust me, it will flake off. I have 2 Sigma EX lenses from that generation, and on both the finish is starting to flake off.

I used this lens for a couple years on crop sensor cameras as well as the 5D, and it handled well on both.

I just recently picked this camera up about 2 months ago, and its bloody brilliant. A local camera shop was selling it used for $600, and I couldn't resist because at that price it was a steal.

Overall, I'm very impressed with this camera. I currently also shoot with the 5D, and the 1D IIn, so I'm used to the 1D series bodies and full frame performance, and I was not at all let down by the 1DSII. It is very fast and responsive, great build quality, and the weather sealing is fantastic. The 16.6 MP RAW files are beautiful at every ISO stop, and provide lots of detail and room to push and pull files.

Some people complain about the 2 button operation of the older 1D cameras, but I actually like it, and don't find it a bother at all. I guess its all about what you are used to.

My biggest issues are:
1. Limited ISO range, but the what is there is fantastic. (50-3200) I've also pushed it a stop in post to 6400 on occasion. I think the 5D retains a little bit more data for pushing at 3200 since I've pushed the 5D to 12800, but there is still ample data on the 1DSII.

2. Buffer size. Yes, I know that 16.6 MP RAW files are large, and its an old camera (pre-UMDA support), but I'm still going to complain a little. You only get 10 frames before the buffer fills when shooting RAW, but I haven't had that issue too many times. When it happens, it seems to clear the buffer pretty fast any way. It's certainly a lot better than the EPSON R-D1. That you only get 2 frames before the buffer fills.

3. Old battery technology. You have to discharge and recharge the battery since its an old NiMH design. It lacks the wonderful Li-Ion tech of the 5D. (Side note: A fully charged battery gives me anywhere from 3,000-4,000 shots though, so I can't complain about that!)

Overall, a wonderful camera, and the detail and resolution is amazing. It feels great in the hand, has an amazing viewfinder and AF system.

Oh, and the quiet mode on the camera is really quite nice and useful for noise sensitive events.

This is an amazing camera. I picked it up as a second body. My main body is a gripped 5D. I love the way the 1D series feels. It just is amazing. The AF system on this camera is a huge step up from the 5D, and the 8.5 fps is quite stunning. There is almost no shutter lag.

The weather-sealing on this camera is great, and the build quality is amazing.

3 issues.

1. High iso performance. 1600 is usable but needs some work, and 3200 is pretty much junk, especially when compared to the 5D. Its about a full stop behind as far as noise, and the tonal range is not as good. I did figure out that if you pull the shadows back in lightroom and the blacks down, it really helps a lot, and gets rid of that purple hue in the shadows.

2. The AF system in low light is not as quick as the 5D's center point in low light. I found this quite shocking. I would have thought the fancy 45 point system would have no trouble, but it does.

3. Old battery technology. You have to discharge and recharge the battery since its an old NiMH design. It lacks the wonderful Li-Ion tech of the 5D.

A very nice and sharp lens with great colors and contrast. Nice bokeh as well thanks to the constant f/2.8 aperture. In the day, the auto focus is accurate and does not hunt.

However, at night, the AF tends to hunt in low light. The auto focus is slow no matter what time of day, and it is very noisy because it is driven by a DC motor.

The build quality is not that wonderful. Made of plastic, it feels cheap, especially when compared to Canon L lenses, and mid-range lenses. It still feels cheap when compared to the new Tamron 24-70 f/2.8 VC, and the new Tamron 70-200mm f/2.8 VC.

Overall, a nice lens, with the 2 issues being build quality, and AF speed. The optics are incredible, and on par with the Canon 17-55mm f/2.8 USM IS, and it is much better than the Tamron VC version.

Nice screen, reasonable fps, average iso performance for a crop, great video quality

Cons:

average iso performance for a crop, sub-average af system, plastic based body but still good build quality.

This makes a good second second body, and a wonderful camera for video. It handles well, and the movable screen is very useful for video. The screen has a high-resolution, and you can actually see details on it.

The AF system is pitiful. 9 points? Really Canon? How long have you been using that stupid 9 point system? The 60D's don't seem to be as accurate as the 5D, and the files don't look anywhere near as sharp as the 5D Mark 1. (yes, full frame compared to crop. Its like apples and oranges) But, the 60D has 18mp, so you'd think it would be pretty sharp, but its not. It just isn't. Maybe I got a bad copy, but I've never been impressed. Its good enough, but thats it.

The video however looks wonderful. I bought this mainly as a backup camera/main video camera. The video is sharp, with great colors and contrast.

Other than the AF system and my pickiness towards sharpness, this actually is a pretty good little camera, with wonderful video functionality.

I love this camera. The files that this camera produces are amazing. Low noise at all ISO values, including 3200. I have under-exposed 1 stop at 3200, and boost to 6400 in post, and it still is usable.

The colors are amazing, and the level of detail is incredible. The files from this are way sharper than my 18mp Canon 60D. ISO 50 is a very nice as well. Silky smooth with no noise.

The dynamic range is wonderful, with great highlight recovery in raw files, as well as shadow detail. The shallower depth of field achieved from a full frame vs. a 1.6X crop is very nice as well.

Cons:
Not weather-sealed, but I have shot in light to moderate rain many, many times, and it doesn't seem to care. The AF system is a little weak, especially compared to a 1d series body, but the center point is always fast and accurate. It also has 6 assist points used during af servo mode which work quite well for sports. I have shot several sporting events with it and the 70-200L with out any issues.

Overall, this is an amazing camera, and in my opinion still holds its ground today, and beats any crop camera on the market.

This lens lives on my camera most of the time. I love the 50mm focal length, its just right. The image quality is great, and the bokeh is quite lovely, but the build quality is sub-par. Its not even on the same level as the EF 85mm f/1.8 USM, and the EF 28mm f/1.8 USM, which in my opinion, it should be on that level at least. The price is very similar to both the 85mm and the 28mm.

My next compliant is the lousy AF motor. It says "ultrasonic" on the lens, but its actually a micro-USM, so its not as fast or durable as a real USM motor, and isn't as accurate in low light. Its also not quiet. You can hear a slight wiring of gears as it focuses. I would have been more than happy to pay $50-$100 more for a lens with a real a real USM motor in it like the 85mm and the 28mm.

Other than the build quality and the AF motor, I love this lens. Its sharp, great colors, and marvelous bokeh.

Sharp, Fast and quiet AF, Great Build Quality, Very good Bokeh, Weather-Sealed

Cons:

AF sometimes hunts on my 5D, even in daylight.

This lens is sharp, and has some beautiful bokeh. I shoot with a 5D, and it is wonderful on a full frame camera. It has now replaced the 28mm f/1.8 as my walk-around lens.

The build quality is incredible. It really is built like a tank, and the reverse zoom design is genius. My only complaint is that it occasionally hunts a little bit before actually locking on to the subject. I'm using the center point on the 5D, and it can happen under any lighting condition. Maybe I got a bad copy. Most of the time though, the AF is quick, accurate, and very quiet, with no hesitation. It doesn't seem to track as well as the 70-200mm f/2.8L IS either, but it isn't terrible. Just not as good.

I got this lens when it first came out, which is why I paid so much for it. This lens is very sharp wide open across the frame, and produces wonderful colors. This lens also has very good contrast, even when pointed at a light source. It is also fairly resistant to flaring.

Its biggest downside is fairly noticeable CA, but that can be easily removed in post-processing.

Added bonus: It works on Full-Frame! Thats right. I said full-frame. I regularly use this lens on a Canon 5D, and from 14mm-16mm it fills the frame. Corners are a little weak wide open on full frame, but it works very well.

This is an incredible lens. Wicked sharp, and great contrast and colors. The bokeh is is incredible! The AF is fast, accurate, and quiet.

This lens is small and light weight. I normally have it in a jacket pocket when I'm doing street photography so I can swap it with the 50mm that is mounted on the camera.

This lens is great on crop sensor, but shines on a full frame. I normally use this lens on a 5D, but I've used it on crop bodies in the past. This lens is great for just about everything, and is one of my favorite lenses for portraits.

IQ at 200mm wide open is a little weak. Flares very bad when shooting towards a light source even with the hood attached. HEAVY!

I've gotten some brilliant shots with this lens. The IQ is really quite good wide open, except at the long end of the range (~200mm). Its not terrible at 200mm, but its not as good as at 70mm, and no where close to a prime.

This lens is amazing on a full frame. The auto focus is lighting fast and accurate, even on a 5D. Weather sealing is great. I've shot in the rain several times without any problems. IS is great, and very beneficial for a lens of this range.

This is a heavy lens, but it has an excellent build quality. It balances very nicely on a gripped 5D.

This lens is fantastic. I use it on a 5D, and the 2 make a perfect pair. The colors and contrast are excellent. This lens is sharp in the center wide open, but a little soft in the extreme corners. Stop it down a little bit, and everything looks fantastic. The AF is fast, quiet, and very accurate thanks to the USM. This lens does very well in low light. I highly recommend this to anyone who needs a large aperture wide angle lens.

The AF hunts in low light more than a USM lens. Loud AF motor, and not as fast as a USM.

The original 50mm f/1.8 is a fantastic lens. The colors and contrast are fantastic, even when shooting wide open. This lens is very sharp. The build quality is much better than the version II of this lens, and the AF is a more accurate as well. The AF does have a more of a tendency to hunt in low light than a USM, but for an AF-D lens, it's very good. AF is a little loud, but it's not terrible. I highly recommend this lens to anyone who wants a 50mm, but doesn't want to spend a lot of money.